The culture and acclimation of mixed bacteria were studied systematically

including refractory and salt-tolerant acclimation

for hypersaline polluted water from chemical factories which is degradated hardly.The results show that during refractory acclimation

if CODCr removal rate is as a primary factor

asynchronous domestication should be selected because of its CODCr removal rate 72.0%

much higher than that of synchro one.If reagent cost is as a leading factor

the method of rising CODCr load is the best choice

whose agentia cost is only 5.78 CNY·（t water）-1.The method of high CODCr load is characterized by the shortest domestication time of 17 d.Concentration of sodium chloride increases from 50 g·L-1 to 60 g·L-1 by 2 g·L-1

the mixed bacteria adapted hypersaline condition of 60 g·L-1 NaCl after domestication of 20 d

and CODCr removal rate increases slightly

by about 1%.The change of bacteria morphology before and after acclimation

observed by SEM

indicates that the mixed bacteria before domestication is uniform size and surface smooth

and mainly consists of cocci and short bacilli; while that after acclimation is surface rough

mainly consists of long bacilli and contains a lot of secretion

which is a result of acclimatizing themselves to hypersaline environment.